The most common and most likely answer to this crossword clue is the 6 letter word GNARLY
I've seen this crossword clue in The Guardian
G
N
A
R
L
Y
More clues leading to the result GNARLY
Buddy explains!
The straight part
We know that "bent like an old man" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case bent like an old man = gnarly.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does GNARLY mean?
GNARLY adjective- Having or characterized by gnarls; gnarled.
- Excellent; attractive.
- Dangerous; difficult.
- Unpleasant, awful, ugly.